A common fluid connection comprises a first coupling component, a second coupling component, and a coupling nut which draws the coupling components together. The inner faces of the first and second coupling components are disposed in an end-to-end relationship to provide a through-path between the respective passageways. A sealing bead extends axially outward from the inner face of the first coupling component and a similar sealing bead extends axially outward from the inner face of the second coupling component. A sealing gasket is interposed between the beads, and seals the union between the first and second coupling components.
An accurate positioning of the sealing gasket relative to the coupling components, and particularly to their beads, is important to assure proper sealing. To this end, a retainer is commonly used to hold the sealing gasket in the correct location during assembly of the fluid connection. One popular type of retainer comprises a plurality of legs, which are sized and shaped to bias fit upon a leg-receiving ledge of the first coupling component. A separate sealing gasket can be secured to the retainer or, alternatively, the sealing gasket and the retainer can be integrated into a one-piece unit (see e.g., U.S. Pat. No. 4,650,227). In either case, the sealing gasket and retainer can be attached to the first coupling component via placement of its legs on the leg-receiving ledge, and the second coupling component is then assembled to the first coupling component to complete the fluid connection.
In the past, different designs for sealing gaskets and retainers have been proposed, developed and/or commercialized, and most of these designs are believed to perform adequately with respect to sealing performance. However, the challenge currently facing the industry, is the production of satisfactorily performing parts in an economic, commercially viable manner. This challenge is complicated when a fluid connection is intended for use in semiconductor fabrication systems (wherein contamination is measured on a parts-per-billion basis) as the sealing gasket and retainer must be ultra-clean to satisfy the strict purity standards.